Method and apparatus for controlling water supply in planographic printing press



Jan. 28, 1958 G. R. BRODIE 2, METHOD AND APPARATUS FOR CONTROLLING WATERSUPPLY IN PLANOGRAPHIC PRINTING PRESS Filed Dec. 13, 1954 INVENTOR.George R. Brodie METHOD AND APPARATUS FOR CONTROLLING WATER SUPPLY 1NPLANOGRAPHIC PRET- ING PRESS George Rogers Brodie, Lower MerionTownship, Montgomery (lounty, Fa assignor to Fredk H. Levey Company,inc, New York, N. Y., a corporation of New York Application December 13,1954, Serial No. 474,772

4 Claims. (63!. 101-438) This invention relates to the art of printingand, particularly, to improvements in the construction and operation ofweb-fed multi-color printing presses adapted to print from planographicprinting plates. More particularly, the invention relates to the controlof the rate at which water is applied to the respective plates.

The surfaces of planographic printing plates are generally bimetallic,one metal having the characteristics of being wet with Water and theother having the characteristics of being wet with ink, as is wellunderstood in the art. In printing from such plates, water is firstapplied to the plate surface and thereafter ink is applied, as by meansof separate rollers, the surfaces of the rollers being wet with waterand ink respectively and rotating in contact with the plate surface.

The rate at which water must be applied to the plate surfaces foroptimum printing quality is rather critical and must be carefullyregulated and controlled. It all depends, in part, upon the area of thenon-printing surface of the plate. The required amount of water to besupplied to a plate during normal printing time is substantially lessthan that required during the starting-up period of the press and,therefore, adjustments for optimum starting-up conditions must becarefully made each time the press is put in operation and, when theplates have been properly wetted, the adjustments must be carefullychanged so as to supply water thereto at a rate just sufiicient tomaintain optimum printing conditions.

In multi-color printing, a plurality of such planographic plates isused, one for each color and, since the area of printing surface isusually very different for one color than for another color, the rate atwhich water is applied to each plate must be carefully adjusted toattain optimum printing conditions when starting up the press andseparate readjustments must be made for each cylinder to maintain thoseconditions during normal operation of the press.

In modern press design it has been customary to apply the water to eachplate cylinder by means of rollers operating in contact with the platesurface thereon, and to supply the water to the respective rollers bymeans of separate fountain rollers, the rate at which water is suppliedto each plate surface being controlled by adjusting the speed ofrotation of the fountain roller associated therewith.

In multi-color printing on web-fed presses it is not unusual to use asmany as five difierent colors, thus requiring five separate platecylinders to which water must be supplied at different rates, bothduring normal operation and during the starting-up of the press. Thusseparate adjustments must be made in starting the press and bringing itto normal operation. These adjustments have been time-consuming andexpensive, particularly where frequent stopping and starting of thepress has been necessary.

My present invention provides improved method and means for controllingand regulating the rate at which the water is supplied to printingpresses of the multi-color aired tates ten ice web-fed type, justdescribed, whereby separate adjustments of the speed of rotation of eachfountain roller can be made for optimum printing conditions during thestarting-up period and a separate adjustment can be made for each of thefountain rollers for normal operation, without disturbing the first setof adjustments, and the speed of rotation of the respective fountainrollers can be switched simultaneously and automatically fromstarting-up operation requirements to normal operation requirements orvice versa.

My invention will be further described and illustrated with reference tothe accompanying drawing which represents diagrammatically andconventionally an embodiment of my invention in a web-fed multi-colorrotary type press. For simplicity, only three plate cylinders have beenshown, but it will be understood that the invention is applicable toprinting presses containing any number of plate cylinders in excess ofone.

In the drawing, the impression roller is indicated at 1 and the platecylinders are indicated at 2. Planographic printing plates are securedto the surfaces of the cylinders 2 by means well known to the art, andare wetted with water by passing in rolling contact with the surfaces ofrollers 3 to which water is supplied by rollers 4 operating in contactwith the fountain rollers 5, the lower surfaces of which are submergedin water maintained at a constant level in the fountains 6.

After water has been applied to the plates, as just described, ink isapplied thereto by means of form rollers 7 and thereafter the surfacesof the plates 2, which have been Wet with water and then with ink, passin contact with blanket cylinders 8 which pick-up and apply the ink tothe web 9 passing about the impression cylinder 1. In passing to andfrom the impression cylinder, the web passes over idler rollers 10.

Each fountain roller is driven by a separate motor indicated at 11. Forsimplicity, I have in the drawing indicated a direct coupling of thedrive shaft 14 of the motor with the shaft of the fountain roller.However, any suitable means for driving the fountain roller by the motormay be used, including reduction gears.

The motors 11 are, with advantage, of the hydraulic type and each isconnected with a fluid pump 15 by means of conduits 16 and 17 throughsupply lines 18 leading to the motor and discharge lines 19 leading fromthe pump. Efiiuent liquid from the motors is passed through lines 20 toreservoir 21 with which the pump is connected through line 22.

Positioned in each of the lines 16 and 17 adjacent each of the motorsare flow control valves 23 and 24, respectively. I have also, withadvantage, placed check valves 25 and 26 in these respective linesbetween the flow control valves and the motor.

Positioned in line 17 adjacent the pump is a shut-01f valve 27 andsimilarly positioned in line 16 is a shut-off valve 28. Also positionedin line 19 adjacent the pump is a relief valve 29.

With the press in normal operation, I may, for example, close valve 28and open valve 27, thereby causing the motivating fluid to flow from thepump to the respective motors through lines 17. I then adjust each ofthe valves 24 so as to regulate the speed of the motor asso ciatedtherewith to drive the fountain roller 5 at a speed such as to deliverthe optimum amount of water to the plate cylinders through rollers 3 and4 under normal operating conditions. I may then close valve 27 and openvalve 28 and similarly adjust the respective valves 23 so as to operatethe motor at a speed at which the optimum amount of water is deliveredto the plate cylinder associated therewith under starting-up conditions.

Having thus adjusted each of the valves 23 and 24 for a particular pressset-up, the adjustments need not be I 3 disturbed so long as thatparticular press set-up is being used, regardless of press shut-clownsfor purposes other than changing the press set-up.

In starting up the press, the valve 27 will be closed and the valve 28opened, so as to operate the respective motors at the predeterminedspeed to supply the required larger amount of water to the respectiveplate cylinders. When normal operating conditions have been attained,the valve 28 is closed and the valve 27 opened, thus simultaneously andautomatically switching from the adjustment of valve 23 to that of valve24 without in any Way disturbing any of those adjustments.

While I have shown separate control valves 27 and 28, it will beunderstood that in place thereof 1 may use a single three-way valve forswitching the flow of motivating fluid from conduit 16 to conduit 17, orvice versa, as required.

The valves 27 and 28 may be either manually or automatically operated.In either event, no tedious, timeconsuming adjustments need be made andthe entire press canreadily be switched from one condition to the othersubstantially instantaneously.

Since the peripheral speed of the rollers 3 and 4 is dependent upon theperipheral speed of the plate cylinders 2, it is usually necessary thatthe fountain rollers 5 be so constructed and arranged that theirperipheral speed is independent of the speed of rotation of rollers 4.This is, with advantage, accomplished by the use of fountain rollers ofthe brush or loop type. It will be understood that the invention is notrestricted to the particular arrangement of the water train shown in thedrawing, but that other types of Water-supplying means may be usedwhereby the rate at which the water is supplied is de pendent on thespeed of operation thereof.

I claim:

1. In conjunction with a multi-color, web-fed printing press comprisinga plurality of plate cylinders, adapted to hold planographic printingplates in position during printing, and means for separately applyingWater to the plates on the respective plate cylinders by which the rateat which water is applied to the respective plates may be varied byvarying the speed of operation of the Watersupplying means associatedtherewith, a plurality of fluid motors each mechanically connected todrive one of the water-supplying means, a fluid pump, a conduit leadingfrom the pump, a shut-off valve positioned in said conduit, connectionsleading from the conduit beyond said valve to each of the motors, a flowcontrol valve positioned in each of said connections, a second conduitleacing from the pump, a shut-off valve positioned in said conduit,connections leading from the second conduit at a point beyond the valveto each of the motors, and a flow control valve positioned in each ofthe last said connections.

2. A printing press adapted to use in multi-color printing fromplanographic printing plates and comprising a plurality of platecylinders each adapted to hold a plate in position during printing,means for separately applying water to the plates on the respectiveplate cylinders including a fountain roller, whereby the rate at whichthe water is applied to the plates on the respective cylinders is variedby varying the speed of rotation of the associated fountain roller, aplurality of fluid motors, each mechanically connected to drive one ofthe fountain rollers, a fluid pump, a conduit leading from the pump, ashut-01f valve positioned in said conduit, connections leading from theconduit beyond said valve to each of the motors, a flow control valvepositioned in each of said connections, a second conduit leading fromthe pump, a shut-off valve positioned in said conduit, connectionsleading from the second conduit at a point beyond the valve to each ofthe motors, and a flow control valve positioned in each of the last saidconnections.

3. In the process of multi-color printing from a plurality ofplanographic printing plates to which water is applied prior to theapplication of ink thereto at rates dependent on the speed of operationof the water-supplying means, the method of regulating the rate at whichwater is applied to the respective plates during the starting-up periodand during normal operation of the press, which comprises providingalternate paths by which motivating energy is supplied to thewater-supplying means, separately adjusting the rate at which water isto be supplied to the respective plates during the starting period ofthe press by adjusting the amount of energy supplied to the respectivewater-supplying means over one of said paths, separately adjusting therate at which water is to be supplied to the respective plates duringnormal operation of the press, without disturbing the first adjustments,by adjusting the amount of motivating energy supplied to the respectivewater-supplying means over the second of said paths, passing themotivating energy to the respective water-supplying means over the firstsaid path when starting the press and switching the motivating energy tothe second said path when normal operating conditions have beenattained.

4. In the operation of a multi-color rotary printing press in whichwater is supplied by a plurality of fountain rollers to separateplanographic plates and the rate at which the water is supplied to therespective plates is regulated by regulating the speed of rotation ofthe associate fountain roller, each fountain roller being driven by aseparate fluid motor, the steps comprising providing two alternate pathsby which the motivating fluid may be supplied to each of the motors,adjusting the rate at which the fluid is to be supplied to each of said1110- tors over one of the paths to apply the required amount of Waterto each of said plates during the starting-up of the press, separatelyadjusting the rate at which the fluid is to be supplied to each of themotors over the second of said paths to apply the required amount ofwater to the respective plates during normal operation of the press,without disturbing the first said adjustments, passing the fluid to therespective motors over the first said path while starting the press andswitching the fluid to the second of said paths when normal operatingconditions have been established.

References Cited in the file of this patent UNITED STATES PATENTS2,230,503 Roesen Feb. 4, 1941 2,233,210 Huck Feb. 25, 1941 2,690,120Burroughs Sept. 28, 1954

